The present invention relates to the formation of recessed cigarette filters, and more particularly to the on line formation of filters that include smoke altering particulate material such as catalysts, adsorbents, flavors and the like.
Many filter making procedures include combining a number of independent filter components fabricated beforehand, stored and then combined into a particular cigarette filter design, such as a plug-space-plug configuration. Such procedures require a number of steps which can be eliminated with on line formation of the filter components, such as the step of storing the preformed filter components before assembly.